The present invention relates to a heat-dissipating, structure for a switching power supply.
As switching frequency become higher, the structures of the power transformer, choke coil, and smoothing capacitor, which take up a considerable volume, can be made smaller, making it possible to miniaturize the switching power supply.
However, as frequencies becomes higher, the circuits and the circuit elements of a printed circuit board produce more heat.
In a power source where the input and output sides are insulated by a power transformer driven by a switching element, such as a monolithic or inverter system, a measure is taken to reduce the heat generation on the input side mostly by improving the oscillating circuit, but there is almost no improvement for the circuits on the output side.
As a result, the circuit on the output side produces considerable heat, and a for dissipating heat is still required. Thus although the sizes of the components and circuit elements are being reduced, the miniaturization of the power source supply as a whole has not made progress as anticipated.